Air heater and inducer for furnaces



Feb. 3, 1925. 1,525,419

E. H. SWIFT AIR HEATER AND INDUCER FOR FURNACES Filed July 1 1923 mum- Aiii" . EdwinHSwi i. 61 $51 Snow; I f

gnvcmboz a furnace.-, A fifth object of the invention Patented Feb. 3,1925.

EDWIN H. SWIFT, OF BROOKLYN, NEW YORK.

AIRHEATEE AND INDUGER FOR FURNACES.

Application filed. July 18, 1923. Serial N0.'G52,362.

To all whom it may concern:

Be it known that I, EDWIN H. Swrr'r, a citizen of the United States, andresident of the borough of Brooklyn, city of New York, in-the county ofKings and State of NewYorlnhave invented certain new and useful AirHeaters and Inducers for Furnaces, of which the following is a specification.

This invention relates to an air heater and inducer for a furnace;

The object of the invention is thepro'duction of a device and a. method,by means of which heated air is supplied to the unconsumed products ofcombustion of the fuel of a furnace to secure complete combustion. Asecond object of the invention is to provide heated air to the burningfuel of a furnace at a velocity of inflow, by means of which the oxygenof the infiowingair will combine with the unconsumed gases generated.and therefore not chill the bed of the fuel in the furnace. Athirdobject ofthe invention is the production of means and steps whereby allportions of an inflow of air to the combustion chamber of a furnace isheated, before mixing with the gases generatedtherein. A-fourth objectof the invention is to prevent the escape of obnoxious gasesfrom thecombustion chamber of is to provide means, whereby 'an inflow of air.for the combustion chamber o-f a furnace is discharged therein in allportions thereof.

The organization of the invention comprises an induction tube for aninflow of air,

adjustably connected to the door of a. furnace and of a length to enablethe air that flows therethrough, to be discharged between the axialcenter of the furnace and the frontwall thereof. A heating coil islocated in the tube to give the inflowing air a twirling movement, andopenings are formed in the-induction tube for the inflow of heated airand gases to the inside of the said tube, to mix with the air flowingthere through, before entering the combustion chamber of the furnace. inaddition to the heat that is transmitted from the fuel of the furnacethrough the wall of the induction tube. r v t I In the accompanying Idrawings Fig. 1 represents a vertical axial section of-a portion of afurnace, with aside elevation of the air heater and inducer, indicatedin full lines in its operative position, with the barrel oft-the latterindicated in its withdrawn position in dotted lines, Fig. 2 shows anenlarged top plan view of the air heater and inducer; Fig. 3, indicatesa partialsection of Fig. 2'on the line 3, 3; Fig. 4 represents a lefthand side view and section of Fig. 3 on the line 4, 4 and Fig. 5 shows a6 section of Fig. 3 on the line 5, 5.

In general terms the air heater and inducer comprises an induction tubedesig' nated in its entirety by the letter A, which has detachablyconnected thereto. at its outlet end the flared outlet nozzle designatedin its entirety by therletter B. A heating coil designated in itsentirety by the letter C, is detachably secured within the inductiontube; The induction tube A is detachably supported upon the arcuatesupport designated in its entirety by the letter D. and

is detachably fastened to the door ofthe furnace for which the airheater and inducer is used.

A furnace is indicated in its entirety by the letter F, and comprisesthe combustion chamber 20. the grate 21, the front wall 22, the rearwall 23, the ash pit 24,'the furnace door 25, the furnace door opening26, the ash pit door 27, and the ash pit door opening28. l m

The induction tube A is preferably cylindrical and has formed therewithat one end the flared inlet nozzle 30. Rectangular inlet openings 31 areformed in the lower position of the tube'A and openings 32 are formed inits sides, while pairs of openings 33, 34. .35 and 36 are formed in thecrown and bottom of said tube. A damper 38 is provided for the tube -Aadjacent to the inlet nozzle 30. The damper-is supported on the spindle39. the ends of which are journaled in the wall of .said tube. Anoperating endofthe spindle 39', and extension 42 is fastened to theother end of'the said spindle. Longitudinal supporting and track flanges43. extend from the sidesof the tube'A and a bearing discflange 44 alsoextends from said tube.

The flared outlet nozzle B has formed therewith the sleeve 45 having,openings 46. A split pin 47 extends through the openings 46, and in thisinstance through the openings 35, 36 of thetube A, to detachably securethe nozzle B to said tube.

The heating coil Q in this instance com an arm 41 with an prisesa'coreof;a pair of wires 48; 49 wound on each other and has formed atone end an eye 50 used for handling the coil, while adeye 51. The coilin this instance is double threaded and consists of-a series ofri-ngs-54 extending from its core. The rings follow each other in ahelical-direction in said induction tubeA, from adjacent to the door 25locking ring,68 has'extending therefrom the annular locking flange 69,and, an operating: lug 70 with the locking shoulder 71 is formed withthe locking ring 68. V The lock? ing ring 68 is hinged to thehingepmember 61' byv means offthezhinge bolt .72, which latter alsoextends throughthe door 25.

The front plate 61 is, fastened to the furnace door 25by means of thebolts 7 4.

Theinduction tube A, is seated in the arcuate member 60 D, with itsflange outer face of the frontplate 61 above the annular flange 62. a

The locking flange 69 of the, locking ring 68 is swung to its closedposition to lock in place the flange 44 of the tube A, the operating lug7 04 being located beyond the stop lug 64.

To swingthe door 25 of the furnace. F to either its. open. or closedposition, the flange 44 of the tube A is unlocked from the door 25, byswinging up the annular locking ring 68, and moving the induction tubeoutwardly as indicated in, dotted lines in Fig. 1, so; that theoutletnozzle B" will clear and swing in the furnace/door opening26'. V l

To use the air heater and inducer, the door 25; of'the' furnace F is.opened and the induction tube A is located upon the supporting; andtrack flanges 43,0f" the arcuate support D', in its withdrawnpositionasindica ed, in dotted lines in Fig. 1, afterwhich the door 25is closed. Next the locking uring is swung to its closed position, sothat the locking flange 69 thereof will lock the disc flange 44 Of'theinduction tube in place. The length of the said induction tube ispreferably made to-locate'the outlet end of the outlet nozzle Bvbetweenthe axialjcenter of the-furnace-and its front wall22. The damper 38 isnow swungopen to permit the required volume of air to, flow through theinduction tube int-or the combustion chamber 20 at the requisitevelocity. The Y air as it acent to the other endzis-formed as second .ofthe arcuate support 44 hearing against the .said tube h means theinduced air isthoroughly-heated throughout all portions thereof, beforeit enters the combustion chamber 20' of the furnace F, and is deliveredin proper condition therein, for the,combustion of" its oxygen with theunconsumed' gases ofthe products of combustion. By this means perfectGO'HIbLIStlOII'lS obtained with a great saving of fuel andobnoxiousgasesare; pre

vented. from escaping from the furnace. The arcuate support D slidablysupports the induction tube A, so that, the outlet end of the outletnozzle B can be-locate'd between the axial center ofi thefurnace F andits front wall, to distribute the strea-m of induced air to allportionsjof, the combustion chamber 20; andi to be enabledto locate saidinduction tube in its withdrawn position, when the door,25;vof"thevfurnac e is to be opened or closed." 7

i It will [be noted that the heating coil C in the-inductio-ntubeAXislocked thereto some ,distance'back from theouterendlthereof, throughthe second eye 51, to beenabled to extend the windings-of the; coil tothe outer end ofjthe tubeAi B'y' this constru'c tionpracticallytl1e;whole heating valueof the coil is obtained Variousmodifications-may be madein the invention without departing-from thespirit thereof, and the present exemplification is; to be taken asillustrative and not limitative.

Having described my invention what I desire to secure byLetters-Patentandclaim 1s:-

1. In an air heater and ind'ucer the-combination of an induction tubeextending through an opening in the door'of a furnace, said tube havingopenings in its wall," an outlet nozzle detachably connected to theoutlet end of the tube, a heating coil d'e tachably secured in theinduction tubesaid coil comprising'a core withaseriPs-ofrings extendingtherefrom, said rings following each other ina helical path, and meanstodetachably lock the induction tube to the door of the furnace.

2.,In an air heaterjand inducer the combination of aninduction tubeextending through an opening in theidoor of'a furnace, aving openings inits wall, an outlet nozzle detachably connected to" the outlet end ofthe tube, a heating coil detachably secured in the induction tube saidcoil comprising a core with a series of rings extending therefrom, saidrings following each other in a helical path, a damper in the tube and alocking device to lock the induction tube to the door of said furnace.

3. In an air heater and inducer the combination of an induction tubeextending through an opening in the door of a furnace, said tube havingopenings in its wall, an outlet nozzle for the tube, a helical heatingcoil in the tube extending from adjacent to the door of the furnace tothe end of the tube said coil comprising a core with a series of ringsextending therefrom, said series of rings following each other in ahelical path, means to detachably lock the coil at a distance spacedfrom its end of the tube and means to detachably lock the induction tubeto the door of the furnace.

4. In an air heater and inducer the combination of an induction tubeextending through an opening in the door of a furnace and having a 'discflange and supporting and track flanges extending therefrom and havingopenings in the wall thereof, an outlet nozzle detachably connected tothe outlet end of the induction tube, a heating coil detachably securedin the tube, a plate with an annular flange fastened to the door of thefurnace, an arcuate support extending from said plate through theopening in the door of the furnace and a locking ring with an annularlocking flange hinged to said plate, said induction tube located uponsaid areuate support with its flanges bearing on the side edges thereof,and the annular flange of said plate and the flange of said locking ringlocking the disc flange of the induction tube to the door of thefurnace.

Signed at the borough of Manhattan, city of New York, in the county ofNew York and State of New York, this 28th day of June A. D. 1923.

EDWIN H. SWIFT.

